#include "BeginnerGeometry.h"
#include "G4Box.hh"
#include "G4SystemOfUnits.hh"
#include "G4LogicalVolume.hh"
#include "G4NistManager.hh"
#include "G4PVPlacement.hh"
G4VPhysicalVolume *BeginnerGeomotry::Construct()
{
    auto nist = G4NistManager::Instance();
    auto material = nist->FindOrBuildMaterial("G4_AIR");
    // solid
    auto solid_world = new G4Box("world", 0.5 * m, 0.5 * m, 0.5 * m);
    // logic
    auto logical_world = new G4LogicalVolume(solid_world, material, "world");
    // physic
    auto physics_world = new G4PVPlacement(
        0,
        G4ThreeVector(0, 0, 0),
        logical_world,
        "world",
        0,
        false,
        0, true);
    return physics_world;
}